[PATCH] Docs for git-show-rev-cache.
[git.git] / show-branch.c
index fc827ee..8b37aeb 100644 (file)
@@ -35,25 +35,25 @@ static struct commit *pop_one_commit(struct commit_list **list_p)
 }
 
 struct commit_name {
-       int head_rev;   /* which head's ancestor? */
-       int generation; /* how many parents away from head_rev */
+       const char *head_name; /* which head's ancestor? */
+       int generation; /* how many parents away from head_name */
 };
 
-/* Name the commit as nth generation ancestor of head_rev;
+/* Name the commit as nth generation ancestor of head_name;
  * we count only the first-parent relationship for naming purposes.
  */
-static void name_commit(struct commit *commit, int head_rev, int nth)
+static void name_commit(struct commit *commit, const char *head_name, int nth)
 {
        struct commit_name *name;
        if (!commit->object.util)
                commit->object.util = xmalloc(sizeof(struct commit_name));
        name = commit->object.util;
-       name->head_rev = head_rev;
+       name->head_name = head_name;
        name->generation = nth;
 }
 
 /* Parent is the first parent of the commit.  We may name it
- * as (n+1)th generation ancestor of the same head_rev as
+ * as (n+1)th generation ancestor of the same head_name as
  * commit is nth generation ancestore of, if that generation
  * number is better than the name it already has.
  */
@@ -65,10 +65,88 @@ static void name_parent(struct commit *commit, struct commit *parent)
                return;
        if (!parent_name ||
            commit_name->generation + 1 < parent_name->generation)
-               name_commit(parent, commit_name->head_rev,
+               name_commit(parent, commit_name->head_name,
                            commit_name->generation + 1);
 }
 
+static int name_first_parent_chain(struct commit *c)
+{
+       int i = 0;
+       while (c) {
+               struct commit *p;
+               if (!c->object.util)
+                       break;
+               if (!c->parents)
+                       break;
+               p = c->parents->item;
+               if (!p->object.util) {
+                       name_parent(c, p);
+                       i++;
+               }
+               c = p;
+       }
+       return i;
+}
+
+static void name_commits(struct commit_list *list,
+                        struct commit **rev,
+                        char **ref_name,
+                        int num_rev)
+{
+       struct commit_list *cl;
+       struct commit *c;
+       int i;
+
+       /* First give names to the given heads */
+       for (cl = list; cl; cl = cl->next) {
+               c = cl->item;
+               if (c->object.util)
+                       continue;
+               for (i = 0; i < num_rev; i++) {
+                       if (rev[i] == c) {
+                               name_commit(c, ref_name[i], 0);
+                               break;
+                       }
+               }
+       }
+
+       /* Then commits on the first parent ancestry chain */
+       do {
+               i = 0;
+               for (cl = list; cl; cl = cl->next) {
+                       i += name_first_parent_chain(cl->item);
+               }
+       } while (i);
+
+       /* Finally, any unnamed commits */
+       do {
+               i = 0;
+               for (cl = list; cl; cl = cl->next) {
+                       struct commit_list *parents;
+                       struct commit_name *n;
+                       int nth;
+                       c = cl->item;
+                       if (!c->object.util)
+                               continue;
+                       n = c->object.util;
+                       parents = c->parents;
+                       nth = 0;
+                       while (parents) {
+                               struct commit *p = parents->item;
+                               char newname[1000];
+                               parents = parents->next;
+                               nth++;
+                               if (p->object.util)
+                                       continue;
+                               sprintf(newname, "%s^%d", n->head_name, nth);
+                               name_commit(p, strdup(newname), 0);
+                               i++;
+                               name_first_parent_chain(p);
+                       }
+               }
+       } while (i);
+}
+
 static int mark_seen(struct commit *commit, struct commit_list **seen_p)
 {
        if (!commit->object.flags) {
@@ -89,7 +167,6 @@ static void join_revs(struct commit_list **list_p,
                struct commit_list *parents;
                struct commit *commit = pop_one_commit(list_p);
                int flags = commit->object.flags & all_mask;
-               int nth_parent = 0;
                int still_interesting = !!interesting(*list_p);
 
                if (!still_interesting && extra < 0)
@@ -104,10 +181,6 @@ static void join_revs(struct commit_list **list_p,
                        struct commit *p = parents->item;
                        int this_flag = p->object.flags;
                        parents = parents->next;
-                       nth_parent++;
-                       if (nth_parent == 1)
-                               name_parent(commit, p);
-
                        if ((this_flag & flags) == flags)
                                continue;
                        parse_commit(p);
@@ -119,7 +192,7 @@ static void join_revs(struct commit_list **list_p,
        }
 }
 
-static void show_one_commit(struct commit *commit, char **head_name)
+static void show_one_commit(struct commit *commit)
 {
        char pretty[128], *cp;
        struct commit_name *name = commit->object.util;
@@ -129,8 +202,8 @@ static void show_one_commit(struct commit *commit, char **head_name)
                cp = pretty + 8;
        else
                cp = pretty;
-       if (name && head_name) {
-               printf("[%s", head_name[name->head_rev]);
+       if (name && name->head_name) {
+               printf("[%s", name->head_name);
                if (name->generation)
                        printf("~%d", name->generation);
                printf("] ");
@@ -141,6 +214,18 @@ static void show_one_commit(struct commit *commit, char **head_name)
 static char *ref_name[MAX_REVS + 1];
 static int ref_name_cnt;
 
+static int compare_ref_name(const void *a_, const void *b_)
+{
+       const char * const*a = a_, * const*b = b_;
+       return strcmp(*a, *b);
+}
+
+static void sort_ref_range(int bottom, int top)
+{
+       qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
+             compare_ref_name);
+}
+
 static int append_ref(const char *refname, const unsigned char *sha1)
 {
        struct commit *commit = lookup_commit_reference_gently(sha1, 1);
@@ -161,7 +246,7 @@ static int append_head_ref(const char *refname, const unsigned char *sha1)
 {
        if (strncmp(refname, "refs/heads/", 11))
                return 0;
-       return append_ref(refname + 5, sha1);
+       return append_ref(refname + 11, sha1);
 }
 
 static int append_tag_ref(const char *refname, const unsigned char *sha1)
@@ -173,10 +258,16 @@ static int append_tag_ref(const char *refname, const unsigned char *sha1)
 
 static void snarf_refs(int head, int tag)
 {
-       if (head)
+       if (head) {
+               int orig_cnt = ref_name_cnt;
                for_each_ref(append_head_ref);
-       if (tag)
+               sort_ref_range(orig_cnt, ref_name_cnt);
+       }
+       if (tag) {
+               int orig_cnt = ref_name_cnt;
                for_each_ref(append_tag_ref);
+               sort_ref_range(orig_cnt, ref_name_cnt);
+       }
 }
 
 static int rev_is_head(char *head_path, int headlen,
@@ -219,12 +310,15 @@ int main(int ac, char **av)
        struct commit_list *list = NULL, *seen = NULL;
        int num_rev, i, extra = 0;
        int all_heads = 0, all_tags = 0;
+       int all_mask, all_revs, shown_merge_point;
        char head_path[128];
        int head_path_len;
        unsigned char head_sha1[20];
        int merge_base = 0;
        char **label;
 
+       setup_git_directory();
+
        while (1 < ac && av[1][0] == '-') {
                char *arg = av[1];
                if (!strcmp(arg, "--all"))
@@ -275,8 +369,6 @@ int main(int ac, char **av)
                        die("cannot find commit %s (%s)",
                            ref_name[num_rev], revkey);
                parse_commit(commit);
-               if (!commit->object.util)
-                       name_commit(commit, num_rev, 0);
                mark_seen(commit, &seen);
 
                /* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
@@ -310,30 +402,44 @@ int main(int ac, char **av)
                        for (j = 0; j < i; j++)
                                putchar(' ');
                        printf("%c [%s] ", is_head ? '*' : '!', ref_name[i]);
-                       show_one_commit(rev[i], NULL);
+                       show_one_commit(rev[i]);
                }
                for (i = 0; i < num_rev; i++)
                        putchar('-');
                putchar('\n');
        }
 
-       label = ref_name;
+       /* Sort topologically */
+       sort_in_topological_order(&seen);
+
+       /* Give names to commits */
+       name_commits(seen, rev, ref_name, num_rev);
+
+       all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
+       all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
+       shown_merge_point = 0;
+
        while (seen) {
                struct commit *commit = pop_one_commit(&seen);
                int this_flag = commit->object.flags;
+               int is_merge_point = (this_flag & all_revs) == all_revs;
                static char *obvious[] = { "" };
 
-               if ((this_flag & UNINTERESTING) && (--extra < 0))
-                       break;
+               if (is_merge_point)
+                       shown_merge_point = 1;
+
                if (1 < num_rev) {
                        for (i = 0; i < num_rev; i++)
                                putchar((this_flag & (1u << (i + REV_SHIFT)))
                                        ? '+' : ' ');
                        putchar(' ');
                }
-               show_one_commit(commit, label);
+               show_one_commit(commit);
                if (num_rev == 1)
                        label = obvious;
+               if (shown_merge_point && is_merge_point)
+                       if (--extra < 0)
+                               break;
        }
        return 0;
 }